Improvements in the design of semiconductor devices consistently involve an increase in both operating frequency and capacity of such devices. In many cases, these improvements are made with little increase, if not a decrease, in the size of these devices. As a result, density of components, such as transistors, on each of these devices has greatly increased. However, advancements in this regard have not been without their own bevy of drawbacks. For example, as operating frequencies and capacities of semiconductor devices have increased, so has the amount of noise generated from the increases in transistor switching, a drawback that has been even more difficult to address as a result of decreases in signal margins associated with higher frequencies and lower power supply voltages.
One typical approach that has been used to reduce unwanted noise has been the use of decoupling capacitors. As a result, high frequency signals may be filtered from power supply voltages provided to, and derived in, semiconductor devices. In particular, with multi-chip modules, capacitors have been placed on respective dies, but are subject to physical limitations of die surface areas. In part because these capacitors often are metal-insulator-metal (MIM) or metal-oxide-semiconductor capacitors (MOSCAPs), to provide sufficient capacitance, the desired sizes of these capacitors are at times too large for the capacitors to be located anywhere but the uppermost position of a die stack. Moreover, in some cases, the largest capacitor physically compatible with a multi-chip module may still not provide a desirable amount of capacitance.
Therefore, there is a need for a capacitive device that provides sufficient capacitance to a multi-chip module.